[Qemu-devel] [PATCH 2/2] qemu-ga: sample fsfreeze-script

[Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>]

Adds sample scripts for --fsfreeze-script option of qemu-ga.
  -fsfreeze.sh: iterates and execute scripts in fsfreeze.d/
  -fsfreeze.d/mysql-flush.sh: quiesce MySQL before snapshot

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
---
 .gitignore                                         |  1 +
 .../fsfreeze.d/mysql-flush.sh                      | 41 ++++++++++++++++++++++
 .../fsfreeze-script-sample/fsfreeze.sh             | 17 +++++++++
 3 files changed, 59 insertions(+)
 create mode 100755 docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.d/mysql-flush.sh
 create mode 100755 docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.sh

diff --git a/.gitignore b/.gitignore
index bd6ba1c..867cb86 100644
--- a/.gitignore
+++ b/.gitignore
@@ -68,6 +68,7 @@ fsdev/virtfs-proxy-helper.pod
 *.tp
 *.vr
 *.d
+!fsfreeze.d
 *.o
 *.lo
 *.la
diff --git a/docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.d/mysql-flush.sh b/docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.d/mysql-flush.sh
new file mode 100755
index 0000000..1704fb0
--- /dev/null
+++ b/docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.d/mysql-flush.sh
@@ -0,0 +1,41 @@
+#!/bin/bash
+MYSQL="mysql -uroot" #"-prootpassword"
+FIFO=/tmp/mysql-flush.fifo
+
+flush_and_wait() {
+	echo 'FLUSH TABLES WITH READ LOCK \G'
+	read < $FIFO
+	echo 'UNLOCK TABLES \G'
+}
+
+if [ "$1" = "freeze" ]; then
+
+	mkfifo $FIFO
+	flush_and_wait | $MYSQL &
+	# wait until every block is flushed
+	while [ "`echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\
+		$MYSQL | tail -1 | cut -f 2`" -gt 0 ]; do
+		sleep 1
+	done
+	# for InnoDB, wait until every log is flushed
+	while :; do
+		INNODB_STATUS=/tmp/mysql-innodb.status
+		echo 'SHOW ENGINE INNODB STATUS \G' | $MYSQL > $INNODB_STATUS
+		LOG_CURRENT=`grep 'Log sequence number' $INNODB_STATUS |\
+			tr -s " " | cut -d' ' -f4`
+		LOG_FLUSHED=`grep 'Log flushed up to' $INNODB_STATUS |\
+			tr -s " " | cut -d' ' -f5`
+		rm $INNODB_STATUS
+		[ $LOG_CURRENT = $LOG_FLUSHED ] && break
+		sleep 1
+	done
+
+elif [ "$1" = "thaw" ]; then
+
+	if [ -p $FIFO ]; then
+		echo > $FIFO
+		rm $FIFO
+	fi
+
+fi
+
diff --git a/docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.sh b/docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.sh
new file mode 100755
index 0000000..b402107
--- /dev/null
+++ b/docs/qemu-guest-agent/fsfreeze-script-sample/fsfreeze.sh
@@ -0,0 +1,17 @@
+#!/bin/bash
+
+# This script is executed when a guest agent receives fsfreeze-freeze and
+# fsfreeze-thaw command when it is specified in --fsfreeze-script/-F option
+# of qemu-ga or placed in default path (/etc/qemu/fsfreeze-script.sh).
+# When the agent receives fsfreeze-freeze command, the script is issued with
+# "freeze" argument before the filesystem is freezed.. And for fsfreeze-thaw,
+# it is issued with "thaw" argument after filesystem is thawed.
+#
+# This script iterates executables in directory "fsfreeze.d" with the
+# specified argument.
+
+cd `dirname $0`
+cd fsfreeze.d
+for x in *; do
+	[ -x ./$x ] && ./$x $1
+done
-- 
1.7.11.7